DTC U0402 00: Error Signal Received From TCM: Notes

WARNING: This page is about a different car, the 2014 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

DTC U0402:00 (VEHICLE CONTROL MODULE) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Error signal received from TCM
Detection condition	Communication error between TCM and vehicle control module (V/C-module)
Fail-safe	Inhibits the Mazda radar cruise control (MRCC) system control Inhibits the forward obstruction warning (FOW) system control^1 ^1 : Enabled depending on malfunction content.
Possible cause	TCM malfunction (selector lever position signal malfunction) Vehicle control module (V/C-module) malfunction
System wiring diagram	Not applicable